Glossary

How to use this page

Each word has a short, plain meaning and a link to the chapter that explains it. The facts and sources are in that chapter.

A

• Ammonia: The sharp smell from rodent pee in dirty bedding. A strong ammonia smell means the room needs more air or more frequent cage changes. see Housing
• Aspen: A hardwood used for bedding chips. Use aspen or paper bedding, and never cedar. see Housing
• AVMA: The American Veterinary Medical Association. Its euthanasia guidelines (2020 edition) are the standard reference for ending an animal's life humanely. see Humane euthanasia and freezing

B

• Biosecurity: The habits that keep germs and pests out of your colony: quarantine, a closed colony, keeping wild mice out, and separate tools and gloves. see Health and safety

C

• Cage card: A card on each breeding cage. It lists the cage number, line, both parents with their birth dates, the date paired, and every litter. see Running a colony
• Closed colony: A colony where new breeders come from your own animals. Outside animals come in only after quarantine. see Health and safety
• CO2 chamber: A clear box that carbon dioxide gas flows into, used for humane euthanasia of adult rodents. It starts with room air, and it has one small outlet so the air pushed out by the gas can escape, and no other gaps. see Humane euthanasia and freezing
• Colony: Your whole group of breeding ASF and their young. see Running a colony
• Colony log: A record with one row for each litter. Each month it shows which females are having litters, which missed one, and how many pups each cage weans. see Running a colony
• Culling: Humanely ending an animal's life, either for the freezer or because it is sick. see Humane euthanasia and freezing

D

• Dam: The mother of a litter. Her ID and birth date go on the cage card. see Running a colony

E

• Euthanasia: Ending an animal's life quickly and humanely. see Humane euthanasia and freezing

F

• F/T: Short for frozen/thawed: a feeder that was humanely killed, frozen, then thawed before feeding. Thaw in a sealed bag, in a container used only for feeders, away from where people store, make or eat food, and never in a microwave used for people's food. see Humane euthanasia and freezing
• Fixation: When a snake gets used to one kind of prey and refuses others. Some snakes that start on ASF refuse rats and mice afterward. see Feeding ASF to snakes
• Flowmeter: A gauge that shows how many liters of gas flow each minute. You need one for CO2, not just a pressure gauge, to set the right flow. The CO2 must come from a cylinder, not dry ice. see Humane euthanasia and freezing
• Fuzzy: A young pup that has started to grow fur, older than a pinkie. Pinkies and fuzzies need long CO2 exposure followed by a physical method, never cooling on its own. see Humane euthanasia and freezing

G

• Gestation: How long a female is pregnant. For ASF it is about 23 days, counted from the mating plug. see The breeding cycle
• Grow-out: A weaned young ASF being raised to a bigger size. Separate grow-outs by sex by about 5 weeks so they don't start breeding. see The breeding cycle

H

• Harem: One male kept with two or more females. This guide's starting groups are one male with two or three females. see Getting started
• Hopper: In this guide, the holder on a cage lid that holds the food block. Some keepers also use the word for a young, jumpy feeder size. see Food and water

I

• Inbreeding: Breeding close relatives, like brother to sister. It isn't instantly fatal, but over generations it tends to cost litter size and vigor. see Running a colony

L

• Lab block: Hard, complete rodent food pellets made for lab animals. It is the main food and stays in the cage all the time. see Food and water
• LCMV: Lymphocytic choriomeningitis virus. Wild house mice can bring it into a colony, and it can make people sick, including with meningitis. see Health and safety
• Line: A family of animals from one source. Getting animals from two breeders gives you two unrelated lines to cross. see Running a colony
• Litter: The group of pups born together at one birth. see The breeding cycle

M

• Mastomys: The science name for the African rodents keepers call ASF, also known as multimammate mice. see Start here
• Mating plug: A small, firm plug left in the female after mating. Gestation is counted from it. see The breeding cycle
• Mites: Tiny bugs that live on the skin. Signs are scratching, scabs and fur loss around the neck and rump. Rodent mites can bite people and reach a snake room. see Health and safety

P

• Pair: One male and one female kept together to breed. see The breeding cycle
• Papilloma: A skin growth. In Mastomys a virus can cause them, and affected animals should not be bred. see Health and safety
• Pinkie: A newborn pup: pink, hairless and with its eyes closed. see The breeding cycle
• Postpartum estrus: Coming back into heat (ready to mate) right after giving birth. ASF females do this about 3 days after a litter. see The breeding cycle

Q

• Quarantine: Keeping new animals in their own cage, away from your colony and your snakes, for about 4 weeks while you check for mites and illness. see Getting started

R

• Retire: To stop breeding an animal. Retire at about 8 litters, at about 1 year of age, or a clear drop in litters, whichever comes first. see Running a colony
• Rigor mortis: The stiffening of the body some time after death. The AVMA notes it is the only single sign that confirms death on its own. see Humane euthanasia and freezing

S

• Salmonella: A germ that feeder rodents, live or frozen, can carry. Freezing doesn't kill it, so wash your hands after handling feeders. see Health and safety
• Scenting: Rubbing a rat or mouse with used ASF bedding so it smells like an ASF. Keepers use it to switch a picky snake back to rats. see Feeding ASF to snakes
• Secondary method: A physical method (cervical dislocation or decapitation) used after long CO2 exposure for pinkies and fuzzies, once the pup no longer responds to a toe pinch. It is also what you use if you're not sure an animal is dead. see Humane euthanasia and freezing
• Sexing: Telling males from females. The gap between the anus and the genital opening is longer in males. see Running a colony
• Sire: The father of a litter. His ID and birth date go on the cage card. see Running a colony

T

• Toe pinch: Firmly pinching a toe to see if the animal reacts. No response to a firm toe pinch is one of the signs used to confirm death. see Humane euthanasia and freezing
• Trio: One male with two females. A trio needs roughly 200 sq in of floor space or more. see Housing

W

• Weaning: Moving pups into their own cage, away from their parents. Wean at about 21 days. Wean earlier only if you can see the pups eating solid food. see The breeding cycle

Z

• Zoonosis: A disease that can spread from animals to people. Salmonella and LCMV are the two this guide covers. see Health and safety